This invention relates to product inspection methods, and particularly to methods for inspecting product and automatically removing unacceptable product from a production line.
There is a continuing need for better methods of removing unacceptable product from production lines. The current emphasis on product quality in all manufacturing fields is strong. One field where product quality is critical is that of primers for ammunition, since misfires in dangerous situations such as police use, combat or certain types of hunting can literally cost one his or her life. In the past there has been visual inspection of primers to determine acceptable quality. However, primers are produced in such enormous quantities that visual inspection is unreliable.
The present invention solves this unreliability of existing primer production methods by rapidly and automatically removing unacceptable primers from a primer production assembly line. The method is applicable to other products by routine mechanical modifications. In particular, the present invention provides:
1. A method of removing product of an unacceptable height from an array of product in a production line, which comprises the steps of:
(a) supporting a quantity of said product in a product carrier in an array of rows and columns; PA0 (b) moving said carrier to a gauging station; PA0 (c) placing said array between a planar plate and an array of gauging members of known height; PA0 (d) uniformly raising said reference plate, relative to said carrier plate and gauging members, to a predetermined height position so as to cause said reference plate to support said product array and said product array in turn to support said array of gauging members; PA0 (e) measuring the height of each gauging member in said array of supported gauging members; PA0 (f) generating a first rejection signal corresponding to each gauge member whose height is not within a predetermined range; PA0 (g) storing all of said first rejection signals; PA0 (h) lowering said reference plate so that said assemblies are again supported by said carrier plate; PA0 (i) moving said carrier plate to a rejection station; PA0 (j) selectively activating a product removal device in response to said first rejection signals so as to automatically remove from said carrier plate only those products corresponding to gauging members which had an unacceptable height during said measuring; and PA0 (k) returning said carrier plate to said production line.